1. Field of the Invention
The present invention relates to a lens barrel unit.
2. Description of the Related Art
Japanese Patent Laid-Open No. (“JP”) 2007-34069 discloses a lens barrel in which a lens holding cylinder has a ring-shaped step larger than an aperture diameter of a cam cylinder, and a top of a straightforward movement cylinder engaged with the cam cylinder projects ahead of a back portion in an image pickup state.
However, the light shielding effect becomes insufficient in JP 2007-34069, as a result of that the light enters an aperture between the top of the straightforward movement cylinder and the back portion of the lens holding cylinder through an aperture between a surface that defines an aperture of the cam cylinder and a front portion of the lens holding cylinder.